The objectives of this work include the synthesis of members of three classes of compounds which have been found to show activity in the cancer chemotherapy screening program. These compounds and others which we propose to study are also of interest from other viewpoints. They are: (a) intermediates for use in the synthesis of compounds expected to have a pentacoordinate hypervalent carbon atom; (b) silicon and phosphorus analogues of these pentacoordinate carbon species; (c) planar ortho-bridged triarylcarbinyl radicals, cations, and anions; (d) sulfurance imines and other types of hypervalent sulfur species containing S-N bonds; (e) radical imitators expected to ecompose through highly polar transition states; and (f) chiral sulfurane reagents for the conversion of racemic or meso-diols to chiral epoxides with substantial enantiomeric excesses.